A208848 Number of non-Josephus subsets of n people.

0, 0, 0, 0, 0, 0, 0, 0, 0, 3, 0, 0, 13, 0, 0, 26, 0, 0, 54, 0, 238, 794, 0, 0, 308, 545, 0

Offset

0,10

Comments

A non-Josephus subset is a subset of people in the Josephus problem of a circle of n people for which no positive integer k exists which removes all those not in the subset first, by starting the count at person 1 and removing every k-th person clockwise.

References

R. L. Graham, D. E. Knuth and O. Patashnik, Exercise 1.26 in Concrete Mathematics, 2nd edition, Addison-Wesley, 1994, pages 26, 501.

Links

Table of n, a(n) for n=0..26.

Index entries for sequences related to the Josephus Problem

Example

For n = 9, the a(9) = 3 non-Josephus subsets are {1, 2, 5, 8, 9}, {2, 3, 4, 5, 8} and {2, 5, 6, 7, 8}.

Crossrefs

Cf. A208849.

Sequence in context: A363033 A321711 A277788 * A277945 A169777 A338464

Adjacent sequences: A208845 A208846 A208847 * A208849 A208850 A208851

Keyword

nonn,more

Author

William Rex Marshall, Mar 07 2012

Status

approved